演示代码:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<link rel="stylesheet" type="text/css" href="reset.css"/>
<style type="text/css">
#box{
width: 100px;height: 100px;background-color: #ff0000;
margin: 200px auto;
/* transition: width 2s; */
transition: height 2s;
/* transition: background-color 2s; */
}
#box:hover{
/* width: 200px; */
height: 200px;
/* background: #00ff00; */
}
</style>
</head>
<body>
<!--
过度:
元素从一个样式变成另外一个样式
必须触发事件才有过渡效果
-->
<div id="box"></div>
</body>
</html>